Conveyor system with dynamic gapping and method of slug building

Abstract

A slug-building conveyor system and method includes providing a conveying surface defined by a plurality of tandem zones, each of said zones including an article sensor and a position encoder. The encoder produces a position signal proportional to movement of articles in that zone. The article sensor senses articles in that zone. A target position is set for an article in a zone as a function of a position of an article downstream of that article in the direction of article flow. The speed of that zone is adjusted to bring the article toward its target position such that gaps between articles are adjusted during transportation of the articles.

1 . A slug-building conveyor system, comprising: 
 a conveying surface defined by a plurality of tandem zones, each of said zones including an article sensor and a position encoder, said position encoder adapted to producing a position signal proportional to movement of articles in that zone, said article sensor adapted to sensing articles in that zone; and    a control responsive to said position signals and to said article sensors for tracking articles in said zones;    wherein said control is adapted to establish a target position for an article in one of said zones as a function of a position of an article downstream of that article in the direction of article flow and to adjust the speed of said one of said zones to bring that article toward its target position such that gaps between articles are adjusted during transportation of the articles.    
   
   
       2 . The system as claimed in  claim 1  wherein each of said zones includes an endless belt and a motor driven roller, said motor driven roller driving said belt.  
   
   
       3 . The system as claimed in  claim 2  wherein said position signal is proportional to movement to said belt in that zone.  
   
   
       4 . The system as claimed in  claim 2  wherein said control is adapted to control the speed of at least one of said belts to bring an article to its target position as it travels through the corresponding zone.  
   
   
       5 . The system as claimed in  claim 1  wherein said gaps between articles are selected from pitch gaps, window gaps or configurable gaps.  
   
   
       6 . The system as claimed in  claim 1  wherein said control defines a data set for each article on said conveying surface.  
   
   
       7 . The system as claimed in  claim 6  wherein said control deletes the data set for an article when that article does not arrive at a zone within an anticipated interval.  
   
   
       8 . The system as claimed in  claim 6  wherein said data set includes at least one chosen from i) article weight, ii) article width, iii) article identification, iv) barcode, and v) radio frequency identification code.  
   
   
       9 . The system as claimed in  claim 2  wherein said motor driven roller comprises a motorized roller.  
   
   
       10 . The system as claimed in  claim 9  wherein said motor driven roller defines said encoder.  
   
   
       11 . The system as claimed in  claim 10  wherein said motorized roller includes rotational position sensors used for application of electrical power to rotate said motorized roller and wherein said control obtains said position signal from said rotational position sensors.  
   
   
       12 . The system as claimed in  claim 1  wherein said endless belt defines a portion of said conveying surface.  
   
   
       13 . A slug-building conveyor system, comprising: 
 a conveying surface defined by a plurality of tandem zones, each of said zones including an article sensor and a position encoder, said position encoder adapted to producing a position signal proportional to movement of articles in that zone, said article sensor adapted to sensing articles in that zone; and    a control responsive to said position signals and to said article sensors for tracking articles in said zones;    wherein said control is adapted to determine anticipated positions of articles on said conveying surface as a function of at least one of said position signals, wherein said control is adapted to determine an actual arrival of an article at one of said zones as a function of said article sensor for said one of said zones sensing that article;    wherein said control is adapted to determine an anticipated arrival of that article at said one of said zones as a function of the anticipated position of that article and to compare the actual arrival of that article at said one of said zones with the anticipated arrival of that article at said one of said zones and to update the anticipated position of that article as a function of said comparing;    wherein said control is adapted to establish a target position for that article as a function of a position of an article downstream of that article in the direction of article flow and to adjust the speed of said one of said zones to bring that article toward its target position.    
   
   
       14 . The system as claimed in  claim 13  wherein each of said zones includes an endless belt and a motor driven roller, said motor driven roller driving said belt.  
   
   
       15 . The system as claimed in  claim 14  wherein said position signal is proportional to movement to said belt in that zone.  
   
   
       16 . The system as claimed in  claim 14  wherein said control is adapted to control the speed of at least one of said belts to bring an article toward its target position as it travels through said one of said zones.  
   
   
       17 . The system as claimed in  claim 13  wherein said control is adapted to adjust the target position of that article such that gaps between articles can be dynamically adjusted.  
   
   
       18 . The system as claimed in  claim 17  wherein said gaps between articles are selected from pitch gaps, window gaps or configurable gaps.  
   
   
       19 . The system as claimed in  claim 13  wherein said control defines a data set for each article on said conveying surface.  
   
   
       20 . The system as claimed in  claim 19  wherein said control deletes the data set for an article when the actual arrival of that article at a zone does not occur within a particular period after the anticipated arrival of that article at that zone.  
   
   
       21 . The system as claimed in  claim 19  wherein said data set includes at least one chosen from i) article weight, ii) article width, iii) article identification, iv) barcode, and v) radio frequency identification code.  
   
   
       22 . The system as claimed in  claim 14  wherein said motor driven roller comprises a motorized roller.  
   
   
       23 . The system as claimed in  claim 22  wherein said motor driven roller defines said encoder.  
   
   
       24 . The system as claimed in  claim 23  wherein said motorized roller includes rotational position sensors used for application of electrical power to rotate said motorized roller and wherein said control obtains said position signal from said rotational position sensors.  
   
   
       25 . The system as claimed in  claim 13  wherein said endless belt defines a portion of said conveying surface.  
   
   
       26 . A method of building slugs of articles, comprising: 
 providing a conveying surface defined by a plurality of tandem zones, each of said zones including an article sensor and a position encoder;    producing a position signal with said position encoder, said position signal proportional to movement of articles in that zone;    sensing articles in a zone with said article sensor;    establishing a target position for an article in one of said zones as a function of a position of an article downstream of that article in the direction of article flow; and    adjusting the speed of said one of said zones to bring that article toward its target position such that gaps between articles are adjusted during transportation of the articles.    
   
   
       27 . A method of building slugs of articles, comprising: 
 providing a conveying surface defined by a plurality of tandem zones, each of said zones including an article sensor and a position encoder;    producing a position signal with said position encoder, said position signal proportional to movement of articles in that zone;    sensing articles in a zone with said article sensor;    determining anticipated positions of articles on the conveying surface as a function of at least one of said position signals;    determining an actual arrival of an article at one of said zones as a function of said article sensor for that zone sensing that article;    determining an anticipated arrival of that article at said one of said zones as a function of the anticipated position of that article;    comparing the actual arrival of that article at said one of said zones with the anticipated arrival of that article at said one of said zones and updating the anticipated position of that article as a function of said comparing;    establishing a target position for that article as a function of a position of an article downstream of that article in the direction of article flow; and    adjusting the speed of said one of said zones to bring that article toward its target position.